The use of polyaspartates in coating compositions leads to certain disadvantages, including inadequate chemical resistance and the need for solvent to give an adequate pot-life. The choice of polyaspartate can affect cure rates, and can be difficult because certain applications require the use of solvent, which is to be avoided. Additionally, it may be difficult to achieve a 1:1 volume ratio, due to the weight differences between the polyaspartate and polyisocyanate.
UV coatings generally also suffer from various disadvantages, such as embrittlement of thick section coating, which leads to shrinkage and cracking. Additional difficulties arise when trying to cure pigmented systems. What is needed is a dual cure coating that overcomes the disadvantages of prior art coatings.